November 8, 2002—CDC’s National Institute for Occupational Safety and Health (NIOSH) has released a report based on surveys of workers in the vicinity of the World Trade Center (WTC) in New York City. Many workers had previously reported persistent physical and mental health symptoms that they associated with exposures from the 9/11 WTC collapse and ensuing fires.
NIOSH surveyed workers at a high school and college near the WTC, and workers at a high school and college more than five miles away from the site to determine rates of physical and mental health symptoms.
The preliminary results of the employee surveys indicate that 4 to 6 months after the terrorist attacks, workers employed near the WTC site had significantly higher rates of irritative, respiratory, and mental health symptoms, as well as lost work time, than similar workers employed less than 5 miles from the site.
Approximately 30% of workers included in this survey reported persistent physical symptoms several months after the initial event. NIOSH explains that the persistence of symptoms in certain persons might be explained by several factors, including differences in the initial exposure, individual susceptibility, existing medical conditions, and factors related to social support or individual stressors.
Approximately one fourth (27%) of staff at the nearby high school and college lost time from work because of physical symptoms experienced after the WTC disaster, compared with 14% at the more distant high school and 16% at the college.
Mucous membrane and respiratory symptoms among the survey participants, the majority of whom were present during the 9/11 attacks, might have resulted initially from exposure to multiple environmental contaminants (e.g., smoke, respirable airborne particles, fine dust, and fire combustion products) gene rated by the collapse of the towers and ensuing fires, according to NIOSH. Information is limited concerning health effects associated with complex mixed environmental exposures (e.g., those that occurred during and after the WTC attacks).
Approximately one third (33%) of the nearby high school and 24% of the nearby college respondents reported symptoms consistent with major depression. Staff at the nearby schools also reported a significantly higher prevalence ratio (23% and 15%) of new physician-diagnosed post-traumatic stress disorder (PTSD) after September 11 as compared with staff at the more distant schools, but rates for allergies, asthma, and depression were not statistically different.
NIOSH concludes that intervention programs should be tailored to address the needs of these workers, and the effectiveness of these programs should be evaluated. Further assessment is warranted to describe the nature and extent of illness in specific working groups and individual medical follow-up in those with persistent symptoms. For more details about the report, visit NIOSH.
